This invention relates to thermally insulated valve actuators for use with valves used in condensate prone conditions, e.g., HVAC valves. Piping and valves used in HVAC systems frequently are thermally insulated with a wrapping material to minimize energy loss and to inhibit the formation of condensation. In this regard, condensation tends to occur with refrigeration/air conditioning systems, such as those employing chilled water.
Valve actuators are provided that extend through the thickness of the insulation to control the valves. On known systems, the extended actuator comprises a shaft that extends from the valve body to an exterior handle. Typically, an adjustable metallic stop on the actuator which is cooperative with a fixed stop on the valve body, i.e., a “memory stop,” is provided to limit the valve to a predetermined range of motion. The memory stop can be adjusted by a tool such as a screw driver that is inserted through the insulation. The high thermal conductivity of metal extension components and of memory stop components results in cold temperatures at the exterior of the insulation, condensation, corrosion, and energy loss.
It is known to have an extension handle of a non conductive material, however, such known valves include plugs that must be removed to access the memory stop. In this regard, they also require tools for adjusting the memory step that are separate from the valve.